The invention is based on a linear unit with a sliding guide for a carriage as generically defined by the preamble to the main claim. One such linear unit is already known from the catalog entitled xe2x80x9cMechanik-Grundelementexe2x80x9d [Basic Mechanical Elements] ""96/""97, page 9-3 published by Robert Bosch, GmbH, Stuttgart. The linear unit comprises a sliding guide and a carriage embodied as a sliding door, which carriage is guided on a guide profile with the aid of slide elements. Along its longitudinal outside faces, the guide profile has grooves in which the slide elements fixed to the carriage can be guided in sliding fashion. The production-dictated tolerances of the guide profile, which as a rule is extrusion molded, require that the slide elements have a large amount of play in the grooves, so that they do not become stuck. For applications that require higher precision, or in other words less play, for example when workpieces are to be positioned, however, these linear units are unsuitable.
Accordingly, it is therefore an object of present invention to provide a linear unit of this type which avoids the disadvantages of the prior art.
In keeping with these objects, one feature of present invention resides, briefly stated, in a linear unit in which devices are provided for adjusting a plate of a sliding guide, and slide elements are movable transversely to a guide direction of a guide profile.
The linear unit according to the invention with a sliding guide for a carriage has the advantage over the prior art that the play of the sliding guide can be adjusted and thus adapted to the specific requirements. It is especially simple in this respect to provide devices in the form of recesses, which are embodied in a carriage and in slide elements and into which a bolt with an eccentrically formed-on peg can be guided. Sliding guides of a simple design can be converted, if grooves in which extensions of the slide elements can be guided are provided along the outside faces of a guide profile. By the embodiment of extensions with slide faces of various sizes for resting on the guide profile, the pressure per unit of surface area can be adjusted. The friction and frictionally dictated wear can be improved by recesses for receiving lubricant. By means of extensions on the slide elements that are adapted to various shapes of groove, a better positive engagement can be attained. Instead of recesses for adjusting the play, an advantageous embodiment provides for forming extensions onto the slide elements. Another advantageous possible modification is, instead of extensions on the slide elements that engage grooves on a guide profile, for recesses to be provided on the slide elements, with which recesses the extensions embodied on the guide profile cooperate.